Lamp inspection apparatus



Dec. 20, 1960 Filed Dec. 26, 1957 D. L. SNYDER ETAL LAMP INSPECTION APPARATUS 5 Sheets-Sheet 1 INVENTORS DONALD L S/VYDH? ROBERTA. l/EU'V/G Dec. 20, 1960 D. L. SNYDER EI'AL LAMP INSPECTION APPARATUS 5 Sheets-Sheet 2 Filed Dec. 26, 1957 INVIINTORS 001/410 L. SNYDER ROBERT A. tZVV/G A77 ENE) Dec. 20, 1960 n. L. SNYDER ETAL LAMP INSPECTION APPARATUS 5 Sheets-Sheet 3 Filed Dec. 26. 1957 r h m: g g

R m w w 00077101. 311706? By X05517 A. lflW/G c I Z ATTDR/fZY Dec. 20, 1960 D. L. SNYDER ETAL LAMP INSPECTION APPARATUS Filed Dec. 26, 1957 v 5 Sheets-Sheet 4 INVENTORS DONALD L. SNYDER RUBEK T A. HLWI6 a F EL vi.

HIE

Dec. 20, 1960 D. L. SNYDER ET AL 2,965,229

LAMP INSPECTION APPARATUS Filed Dec. 26, 1957 5 Sheets-Sheet 5 44 MIN] "T HIM Jul [hi2 :IHHL W DWI/MD L. S/VYDEI? w I m w ATTJ/f/VEY A I NINVENTORS Sylvania Electric Products corporation of Delaware Filed Dec. 26, 1957, Ser. No. 705,326 4 Claims. (21. 209-81) 'Helwig, by mesne assignments, to Inc., Wilmington, Del., 'a

This invention relates to the manufacture of electric lamps and more particularly to the manufacture of photofiash lamps.

In the manufacture of photoflash lamps, the lamp envelope is usually provided with a filling of aluminum foil shredded to filamentary form as the combustible, oxygen as the combustion-supporting gas, and ignition means in operative relationship with respect to the combustible. The lamp envelope is provided with an external and, on large lamps, an internal coating as a safety precaution to prevent fragmentation, since the pressure during combustion rises to values many times initial pressure because the heat developed expands the oxygen gas. The external lacquer coating with which the lamp envelope is provided is usually applied by dipping based lamps, base up, into a clear cellulose acetate solution until the complete lamp envelope and a portion of the lamp base is immersed in the solution. In the mass production of photofiash lamps employing considerable high speed automatic equipment, it has been recognized that a certain number of misses will occur and a small percentage of the lamps may not be provided with a protective coating covering the entire lamp envelope and a portion of the lamp base adjacent thereto.

In view of the foregoing, the principal object of this invention is to detect incompletely coated lamps.

Another object is to provide apparatus for effecting this detection automatically. t

A further object is to provide apparatus for detecting and rejecting defective lamps automatically whereby they are segregated from the good lamps.

These and other objects, advantages and features are attained, in accordance with the principles of our invention, by providin a lamp-carrying conveyor with an inspection station at which an electro-rnechanical inspector checks the lacquer coating on each lamp, temporarily stores the information acquired during the check, and subsequently transmits this information to actuate a rejector at a rejection station to which the lamps are advanced by the conveyor, the actuated rejector effecting the discharge of the defective lamps from the conveyor.

In the specific embodiment of the invention illustrated in the accompanying drawings, v

Figure 1 is a plan view of the apparatus located at an inspection station.

Figure 2 is a side elevational view of the apparatus of Figure l. v 1

Figure 3 is a transverse sectional view of the apparatus of Figure 1, taken along the line 3455, Figure g I Figure 4 is a plan view of the apparatus located at a rejection station. 7 d t U Figure 5 is a front elevational view of the apparatus located at the rejection station. I I v H Figure 6 is a schematic diagram of an electrical circuit associated with each inspecting device and rejecting d evice at the inspection station and the rejection station respectively.

tates Patent Referring now to the drawings, and more particularly to Figures 1, 2 and 3 thereof, it will be noted that each lamp 10 is carried by a pair of jaws 12 and 14 pivotally mounted on rods 16 and 18 respectively on bracket 20 which is attached to mounting plate '22 on chain 24. The pivot rods 16 and 18 are provided with gears26 and 28 respectively, which mesh with one another at all times, A pair of mounting pins 30 project from the inside face of jaws 12 and 14 and support a spring 32 extending therebetween. An a'pcrtured guide 34 is attached to one of the pins 30, the other pin 30 extending therethrou'gh. A pair of cam followers 36 and 38, the function of which will be described hereinafter, are mounted on the top of jaw 12.

Referring now particularly to Figures 1, 2 and 3, it will be noted that each lamp supporting jaw assembly is further characterized by a wheel 40 mounted on bracket 20 and a pair of wheels 42 attached to the chain 24. The wheels 48 of the lamp supporting jaw assemblies ride in track '44 and the wheels 42 of the chain 24 ride in track 46. The relative location of tracks 44 and 46 with respect to one another is such that they steady the heads and define a fixed path through which the chain 24 moves. The tracks 44 and 46 are mounted on support castings 48, two of which are shown in Figure l, which are mounted on and keyed to a main support shaft 50. j

It will be noted from an examination of Figures 2 and 5 that in the specific embodiment of the invention dis,- closed in the accompanying drawings, a dual production arrangement is provided whereby similar mechanisms operate simultaneously on lamps carried by an upper and a lower conveyor chain. Since these mechanisms and their actuating devices are substantially the same, only one of the arrangements will be described in detail.

Indexing means, not shown, advances five lamps at a time on each chain conveyor into the lacquer check position shown in Figures 1, 2 and 3 of the drawings. A common electrical terminal bar 52 is advanced into engagement with the electrical contact on the bottom of the base of each of the five lamps. One end of wire 53 is connected to terminal bar 52 by terminal screw 55, the other end thereof being connected to a source of electrical energy as described more fully below in the description of Figure 6. The common bar 52 is mounted on a bar support 54with an insulator 56 disposed therebetween. Advancement of the bar support 54 is eff fected by a rocker arm 58 which is rotatable about shaft 60 on which it is mounted, the arm 58 being connected to bar su port 54 at 62 (Fig. 3). The bar support 54 is provided with a pair of guide rods 64 projecting rearwardly therefrom near each end thereof. The guide rods 64 extend through and are slidable in support bracket 66 which is fixedly mounted at .its lower extremity on guide rods 68. The guide rods 68 are fixedly mounted in support castings 70 mounted on the main support shaft 50,

As was mentioned above, one end of rocker arm 58 is connected to barsupport 54 at 62. The otherend of rocker arm 58 is provided with a cam follower 72 (Figs. 2 and 3) which rides on a cam surface74 of bracket 76 which isffixedly attached to drive shaft 78. A drive arm casting 80, fixedly mounted on upper and lowerdrive shafts 78 (Fig, 2), is provided intermediate its ends with a tod end 82 which connects it to one endof rocker arm 84 (Fig. 3). The rocker arm 84 is pivo-tally mounted intermediate its ends on rocker arm shaft 86 which is disposed between and supported by castings 70. ,The other 'end of rocker arm 84 is provided with a cam fol-j lower 88 which rides in a track therefor in cam 90 on cam shaft 92, the cam shaft 92'being driven by suitable means not shown. Thus rotational movement ofthe cam shaft 92 is translated into reciprocating movement of the drive shafts 78 through the rocker arm 84 pivoting about the rocker arm shaft 86, and the drive arm casting 80 which is mounted on the upper and lower drive shafts 78. Rearward movement of drive shaft 78 (movement to the left in Figure 3) effects a displacement of cam follower 72 on rocker arm 58 from the pocket 75 in which it is shown since bracket 76 which is provided with cam surface 74 and pocket 75 is fixedly attached to drive shaft 78. Displacement of cam follower 72 from pocket 75 Onto cam surface 74 causes rocker arm 58 to rotate clockwise on its shaft 60 and advance bar support 54 to the position shown in phantom in Figure 3, thus bringing the common electrical terminal bar 52 into engagement with the electrical contacts on the bottom of the base of each of the five lamps in test position.

Rearward movement of drive shaft 78 (movement to the left in Figure 3 also carries plunger support 102 which is mounted thereon with it, the plunger support 102 sliding on guide rods 68. Five plungers 104, in axial alignment with the five lamps held in the five pairs of jaws 12, 14, are supported by and slidably disposed in the plunger support 102. As the plunger support 102 moves forward, carrying the plungers 104 with it, the heads 106 of the plungers 104 move into engagement with the bulbous portions of the lamps 10 immediately after the terminal bar 52 has been moved into engagement with the electrical contacts on the bottom of the base of each of the lamps. At this point in the forward travel of the plunger support 102, the head of a screw 108 projecting therefrom has moved into engagement with a stop button 110 (Fig. l) projecting from a link operating block support 112. The link operating block support 112 is fixedly attached at each end thereof to one end of a link block guide 114 which is slidably supported in a pivot block support 116, the pivot block support 116 being in turn slidably supported on guide rods 68. Since the link operating block support 112 is slidably supported and the plunger support 102 is positively driven by the drive shaft 78, further movement of the plunger support 102 to the left in Figures 1 and 3 after the screw 108 has moved into engagement with the stop button 110 affects advancement of the link operating block support 112. The link operating block support 112 has five link operating blocks 118 attached thereto but insulated therefrom as shown in Figure 1.

As shown in detail in Figures 1 and 3, a plurality (in this case four) of link plungers 120 are pinned to each link operating block 118 and extend into link cartridges 122 at one end thereof. Each link cartridge 122 is provided with an elongated slot 124 out transversely thereof, within which pin 126, extending through link cartridge 122, rides. A spring 128 is disposed within link cartridge 122, one end thereof abutting the inner end of link plunger 120. The other end of the link cartridge 122 is bifurcated and has an electrical contact finger 130 pinned thereto. The electrical contact fingers 130 are pivotally mounted in finger pivot block 132. The five fingers pivot blocks 132 are mounted on the pivot block support 116 which is fixedly attached to guide rods 68. An aligning bar 136 is attached to the tops of and spans the five finger pivot blocks 132. Since the finger pivot blocks 132, on which the electrical contact fingers 130 are pivotally mounted, are mounted on a stationary support, and the link operating blocks 118, to which the electrical contact fingers are mechanically connected through link cartridges 122, are mounted on a slidable support, the forward motion (movement to the left in Figure 3) of the link operating block support 112, induced by the plunger support 102 through the screw 108 and button 110, causes the electrical contact fingers 130, pivoting on the blocks 132 in which they are mounted, to move into engagement with the upper peripheral edges of the bases of the lamps 10.

The apparatus just described, for actuating the electrical contact fingers 130 is provided with a cover 138 attached to the ends of the pivot block support 116 by screws 140. Angle plug 142, attached to cover 138', provides the means through which electrical connections may be fed through cable 144 to terminal block 146 mounted on bracket 148 which is attached to plunger support 102. 7

Referring now particularly to Figures 1 and 3, as was described above, each link operating block 118 has asso ciated therewith four electrical contact fingers 130; These fingers are electrically connected through terminal block 146 to the circuit of Figure 6.

After the lacquer check has been effected on the two groups of five lamps each by the mechanisms shown in Figures 1, 2 and 3, the upper and lower conveyor chains 24 are indexed to bring the lamps into the reject station shown in Figures 4 and 5. Information concerning the condition of the lamps, as detected by the electrical con tact fingers 130, is received and stored in the circuit illustrated in Figure 6 and described below, until the tested lamps reach the reject station. This information is then transmitted to solenoids 152 disposed in housing 154 mounted on brackets 156 attached to the main support shaft 50, the electrical connections from the referenced circuit to the solenoids 152 being made through cable 158. A shrinkage bin 160, provided with five pockets in alignment with the five lamps 10 at the reject station, is also mounted on the main support shaft 50.

If a lamp 10 is detected by the fingers 130 as being defective, its corresponding solenoid 152 is energized when that lamp is at the reject station shown in Figures 4 and 5 and the solenoid plunger 162 is actuated. The actuated plunger 162 moves downwardly, striking cam follower 36 on jaw 12, thereby causing clockwise rotation of jaw 12 about its pivot rod 16. Since, as was described above, gear 26 on rod 16 meshes with gear 28 on rod 18, the clockwise rotation of jaw 12 about its pivot rod 16 causes counter-clockwise rotation of jaw 14 about its pivot rod 18, thus effecting an opening of the jaws 12 and 14 to release the lamp 10 which falls into its pocket in shrinkage bin 160. When the solenoid 152 is deenergized, the plunger spring 164 returns the plunger from engagement with cam follower 36, thus permitting the spring 32 which bridges the jaws 12 and 14 to effect a return thereof to the closed position. Further indexing of the conveyor chains 24 advances the good lamps 10 to an unloading station where suitable means not shown I deflects the several cam followers 38 to effect an opening of the several jaws 12, 14 and discharge of the lamps to a suitable receptacle.

There are ten identical lacquer test and reject circuits wired in parallel, one of these circuits being illustrated in Figure 6. Line 1 is connected to a volt A.C. source, line 3 is connected to a 24 Volt AC. source, and line 5 is connected to a 40 volt D.C. source. When a lamp enters the test position, the normally open lamp test contacts 7 (the electrical contact fingers of Figures 1, 2 and 3) are moved into testing engagement with the lamp base as shown in phantom in Figure 3. If the peripheral portion of the lamp base is covered with a film of protective lacquer, the lamp is good, the circuit through the test contacts and the lamp base remains open, and the lamp moves on without being rejected.

If the pre-determined area of the upper peripheral portion of the lamp base is not covered with a film of protective lacquer, the normally open lamp test contacts 7 will be closed through the lamp base. Cam operated timing switch 9 now closes, thus energizing coil 11 and effecting a closing of its normally open coil contacts 11a. This permits 24 volt AC. power in line 3 to flow through contacts 11a and the closed lamp test contacts 7 and energize coil 13. Energization of coil 13 effects a closing of its normally open coil contacts 13a and 13b. Cam operated timing switch 15 now closes, thus energizing coil 17 and effecting a closing of its normally open coil contacts 17a. This permits 24 volt AC. power in line 3 to flow through contacts 17a and through the previously closed contacts 13a and 13b to keep the coil 13 energized until the lamp reaches the reject station.

When the lamp reaches the reject station, cam operated timing switch 19 closes, thus energizing coil 21 and effecting a closing of its normally open coil contacts 21a. This permits 40 volt DC. power in line 5 to flow therethrough and through previously closed coil contacts 13b and energize solenoid 23 (solenoid 152 of Figure 5), thus effecting rejection of the lamp as described above.

After the lamp has been rejected, cam operated timing switch 15 opens, thus effecting de-energization of coil 17 and opening of its contacts 17a. Opening of contacts 17a breaks the circuit therethrough, and effects an opening of contacts 13a, de-energization of coil 13 and opening of contacts 13b. The circuit is now ready for the next test cycle.

A manually operated, normally open test switch 25 across the normally open lamp test contacts 7 provides a means for testing the circuit since the closing thereof simulates a defective lamp condition. Signal light 27 across lamp test contacts 7 provides a visual means of checking the circuitry therethrough. Similarly, signal light 29 across solenoid 23 provides a visual means of checking the circuitry therethrough. Signal lights 31, 33 and 35 provide a visual means for checking the operation of timing switches 9, 15 and 19 respectively.

What we claim is:

1. Apparatus for inspecting a based electric lamp having an electrical contact on the bottom thereof to determine whether or not a coating of non-conductive material is present on a portion of the electrically conducting base thereof, said apparatus comprising: a lamp holder for supporting said lamp; a plurality of electrically conducting fingers; an electrical terminal bar; means for effecting disposition of said fingers in engagement with the base of said lamp on the portion thereof to be inspected; means for effecting engagement of said terminal bar with said electrical contact on the bottom of said base; an electrical circuit connected to said fingers and said terminal bar, said circuit including means, responsive only to a flow of current through said fingers, said base and said terminal bar, to actuate said lampholder and effect release of the lamp therefrom; and means for energizing said electrical circuit.

2. Apparatus for inspecting a based electric lamp having an electrical contact on the bottom thereof to determine whether or not a coating of non-conductive material is present on a portion of the electrically conducting base thereof, said apparatus comprising: a lampholder for supporting said lamp; a plurality of electrically conducting fingers; an electrical terminal bar; means for effecting disposition of said fingers in engagement with the base of said lamp on the portion thereof to be inspected; means for effecting engagement of said terminal bar with said electrical contact on the bottom of said base; an electrical circuit connected to said fingers and said terminal bar, said circuit including means, responsive only to a flow of current through said fingers, said base and said terminal bar, to actuate said lampholder and effect release of the lamp therefrom; and means for energizing said electrical circuit while said fingers are in engagement with the base of said lamp on the portion thereof to be inspected and said terminal bar is in engagement with said electrical contact on the bottom of said base, whereby a fiow of current through said fingers, said base and said terminal bar will effect actuation of said lampholder and release of the lamp therefrom.

3. Apparatus for inspecting based electric lamps having electrical contacts on the bottoms thereof to determine whether or not a coating of non-conductive material is present on a portion of the electrically conducting bases thereof, said apparatus comprising: a conveyor having a plurality of lampholders thereon for advancing lamps supported by said lampholders to a plurality of stations including an inspection station and a rejection station; a plurality of electrically conducting fingers disposed at said inspection station; an electrical terminal bar disposed at said inspection station; means for advancing said fingers into engagement with the base of a lamp on the portion thereof to be inspected; means for advancing said terminal bar into engagement with the electrical contact on the bottom of said lar'np; an electrical circuit including said fingers and said terminal bar and responsive only to a flow of current through said fingers, said base and said terminal bar to effect detection of the absence of said coating of non-conductive material; an electrical memory means energized by the closing of said electrical circuit; means at said rejection station for opening said lampholders to effect release of a lamp therefrom; and means, actuated by said memory means, for actuating said lampholder opening means.

4. Apparatus for inspecting electric lamps to determine whether or not a coating of non-conductive material is present on a portion of the electrically conducting bases thereof, said apparatus comprising: a conveyor having a plurality of pairs of lampholders thereon, for advancing a plurality of lamps at a time, supported by said pairs of lampholders, to a plurality of stations including an inspection station and a rejection station; a plurality of sets of electrically conducting fingers disposed at said inspection station; means for advancing said sets of fingers into engagement with the bases of the lamps on the portions thereof to be inspected; a plurality of electrical circuits, each circuit including one of said sets of fingers as normally open electrical contacts closable only through an uncoated portion of said base, each of said circuits including means responsive only to a flow of current through said fingers and said base to effect detection of the absence of said coating of non-conductive material; a plurality of electrical memory means each of which being energized only by the closing of one of said electrical circuits; a plurality of means at said rejection station for opening said pairs of lampholders to effect release of lamps therefrom; and means, actuated by each of said memory means, for actuating each of said lampholder opening means.

References Cited in the file of this patent UNITED STATES PATENTS 1,306,811 Gray June 17, 1919 2,407,062 Darrah Sept. 3, 1946 2,488,609 Smith Nov. 22, 1949 2,554,982 Hartley et a1. May 29, 1951 2,653,711 Flaws et a1. Sept. 29, 1953 2,767,675 McGowan Oct. 23, 1956 

